Pre-heat the oven to 180C (390F) fan-forced.

In a large bowl, combine the flour, bicarb, cream of tartar, sugar and salt.

Make a well in the middle then gently stir through the buttermilk.

Fold in the walnuts.

Brush the melted butter over the insides of a 21x10cm (8 ¼ x 4in) loaf tin.

Spread the batter into the tin and smooth out the top.

Pour the remaining butter over the batter.

Bake for 30 minutes then reduce the temperature to 130C (290F) fan-forced and bake for another 30 minutes or until a cake tester inserted in the middle comes out clean.

Transfer the bread to a wire rack to cool completely.

Serve sliced and toasted and spread with butter, jam, honey or fresh ricotta cheese.